Rotary distributor pump



Feb. 10, 1970 E, B, WATSON ET AL 3,494,289

ROTARY DISTRIBUTOR PUMP Filed April 22. 1968 4 Sheets-Sheet 1 5M wry/W9| ATTO EYS Feb. 10, 1970 E. B. WATSON ETAL 3,494,289

I ROTARY DI STRIBUTOR PUMP Filed April 22, 1968 4 Sheets-Sheet 2 Ji/?,INVENTORS z'lw 42 Z L ATTO EYS E. BfwATsoN 'ET AL` '3,494,289

ROTARY DISTRIBUTOR PUMP Feb. '10, 1970 4 Sheets-Sheet 3 Filed April 22,1968 TORS .TSON ARD R. THOMSON 6MM/J INVEN N B. WA

Alllyf mmm l' t Il l ATTONEYS Fb. l0, 1970 E, Q WATSON ETAL 3,494,289

ROTARY DISTRIBUTOR PUMP Fild April 22, 1958 4 Sheets-Sheet 4 q ff 59 8|a2 84 as INVENTORS EDWIN B. WATSON MILLARD R. THOMSON @www ATTORNEYSUnited States Patent O 3,494,289 ROTARY DISTRIBUTOR PUMP Edwin B. Watsonand Millard R. Thomson, Sidney, N.Y., assignors to The BendixCorporation, a corporation of Delaware Filed Apr. 22, 1968, Ser. No.723,089 Int. Cl. F04b 13/00, 23/04, 49/00 U.S. Cl. 103-2 35 ClaimsABSTRACT OF THE DISCLOSURE Rotary distributor type fuel injection pumpfor multicylinder compression ignition engine comprising coaxial rotarytransfer pump, opposed radial piston high pressure delivery pump, anddistributor rotor, and further comprising valve means to regulate thetransfer pump delivery pressure for controlling timing of injection inresponse to engine speed and hydraulically actuated fuel metering valvemeans for automatically governing engine speed.

This invention relates to fluid pumping and distributing apparatus andmore particularly to apparatus for supplying metered quantities ofliquid fuel at high pressure to the combustion chambers ofmulti-cylinder engines.

One of the objects of the present invention is to provide a fuelinjection pump with metering means novelly incorporated therein.

Another object of the invention is to provide novel hydraulicallyactuated means in a fuel pump for automatically controlling theoperation thereof and the speed of an engine with which the same isassociated.

A further object is to provide a novelty constructed fuel injection pumpwhich is smaller and lighter than prior known pumps capable ofperforming comparable functions.

Still another object is to provide novel means in conjunction with anengine fuel injection pump for automatically varying the timing ofinjection in response to pump and engine speed.

A still further object is to provide novel means for automaticallycontrolling, as a function of engine speed, the quantity of fuel perstroke delivered by a fuel injection pump to the combustion chambers ofan engine.

Another object is to provide novel means in conjunction with fuelmetering apparatus in an injection pump for automatically satisfying thetorque backup requirements of an engine supplied by the pump.

The above and further objects and novel features of the invention willmore fully appear from the following detailed description when the sameis read in connection with the accompanying drawings. It is to beexpressely understood, however, that the drawings are for the purpose ofillustration only and are not intended as a denition of the limits ofthe invention.

In the drawings, wherein like reference characters refer to like partsthroughout the several views,

FIG. 1 is a side elevation View of one form of six-cylinder engine fuelpump embodying the present invention;

FIG. 2 is a cross sectional view of the pump of FIG. 1, the sectionbeing taken substantially in a vertical plane containing thelongitudinal axis, as on line 2-2 of FIG. 4;

FIG. 3 is an end view of spill valve 32 as viewed from the left in FIG.2;

FIG. 4 is a transverse sectional view taken substantially on line 4-4 ofFIG. 2;

FIG. 5 is a transverse sectional view taken substantially on line 5-5 ofFIG. 2;

FIG. 6` is a transverse sectional view taken substantially on line 6-6of FIG. 2;

3,494,289 Patented Feb. 10, 1970 FIG. 7 is a transverse sectional viewtaken substantially on line 7-7 of FIG. 2;

FIG. 8 is a detail sectional view taken on line 8-8 of FIG. 9;

FIG. 9 is a transverse sectional view taken substantially on line 9-9 ofFIG. 2, with a portion broken away to show an outlet or deliverypassage;

FIG. 10 is a transverse sectional view taken substantially on line 10-10of FIG. 2;

FIG. l1 is an isometric view on an enlarged scale of the throttle valve;

FIG. 12 is a transverse sectional view taken substantially on line 12-12of FIG. 2;

FIG. 13 is an enlarged scale top plan view of the lefthand portion ofcontrol sleeve as viewed in FIG. 2;

FIG. 14 is a partial sectional View taken on line 14-14 of FIG. 2;

FIG. 15 is a detail sectional view of the pump-distributor rotor;

FIG. 16 is a detail side elevation View of theV metering or spill valve;

FIG. 17 is a detail sectional view of the distributor head; and

FIG. 18 is a detail sectional View of the casing part for housing thecontrol mechanism for injection timing.

A single embodiment of the invention is illustrated in the drawings, byway of example, in the form of a combined fuel pumping, distributing andcontrol apparatus for a six-cylinder solid fuel injection engine. Theapparatus comprises a hollow casing having three main parts 20, 21 and22 (FIG. 2) secured together by bolts 23 and 24. The basic workingcomponents of said apparatus comprise, from left to right in FIG. 2, adrive shaft 26, an intake pressure regulating valve 27, a roller typetransfer pump 28, a radial-piston, high-pressure delivery or injectionpump 29, a combination pump and distributor rotor 30, a plurality ofdelivery valves 31, a combined fuel metering and hydraulic governorvalve 32, a throttle valve 33 (FIG. l0) and a hydraulic timing andtorque backup control mechanism 34. Casing member 21 functions as adistributor head, and rotor 30 functions additionally as a casing formetering valve 32.

Fuel enters the apparatus from a suitable supply source under lowpressure through a passage 36 which intersects an arcuate groove 37(FIG. 5) in the annular shoulder 38 of casing member 20. Groove 37 andhence, passage 36, communicate through arcuate openings 39' in a bimetaldisc or plate 40 with the intake chamber 41 of transfer pump 28. Thelatter may be of any suitable known construction and as shown, comprisesan end plate 42 and a cam ring 43, the inner cylindrical surface ofwhich is eccentric to the longitudinal axis of the apparatus. Plate 42is held in place by split ring 44 anchored in an annular groove incasing 20. Retaining ring 44 may be tapered at the periphery thereof toresiliently wedge plate 42 into firm engagement with cam ring 43. Anysuitable known means, such as a dowel pin 45, may be used to angularlyorient cam ring 43 and plates 40 and 42 in housing 20.

A rotor 46 is mounted -between plates 40 and 42 on a sleeve 47 forrotation therewith. Said sleeve is in turn drivably connected, such asby splines, to drive shaft 26. The periphery of rotor 46 has axiallyextending grooves 48 for seating cylindrical rollers 49. The rotor isconcentrically mounted and hence, together with rollers 49, in a mannerwell understood in the art, forms the low pressure intake chamber 41 anda higher pressure discharge chamber 50 with the rotor turning clockwiseas viewed in FIG. 6. The discharge side 50 of transfer pump 28 is inconstant communication with a drilled passage 51 through arcuateopenings 52 in end plate 40 .nd an arcuate groove 53 in shoulder 38,which groove is ntersected by said passage 51.

At its upper end fuel passage 51 is connected by drilled lassages `54and 55 (FIGS. 2 and 8) to an annular groove i6 in casing member 21within casing member 20, and aid groove is connected to the bore 57through member .1 by six equally angularly-spaced, radial passages 58.fhe latter are adapted to be periodically connected hrough one or moreangular passages S9 (two as shown) r1 rotor 30 to the pressure chamber60 of the high presure injection pump 29 to be next described.

Although pump 29 may be of any suitable known contruction, the same asillustrated comprises a cam ring i1 seated in casing 20 between shoulder62 and the inner nd face of casing member 21, which is angularlyoriented herewith by a dowel 63. Cam ring 61 may be secured in lace by ascrew 64. Rotor 30, which has a close running lt in the bore -of casing21, extends through cam ring i1 and a reduced end portion thereof isprovided with plines for driving engagement with sleeve 47 and hence,vith drive shaft 26. A disc 65 having spring fingers at the leripherythereof may be interposed between split ring l4 and rotor 30 to hold thelatter against the end of disributor head 21. Within cam ring 61 therotor 30 has liametrically disposed enlargements 66 (FIG. 7) in vhich isprovided a transverse cylindrical passage 67 for lidably receiving apair of reciprocable pistons 68. The luter ends of the pistons engageblocks 69 which slide adially in axially extending slots 70 and aregrooved to arry rollers 71 that engage and follow the inner wavy urfaceof cam ring 61. This surface provides three pairs if diametricallydisposed cam lobes whereby the opositely disposed piston-block-rollerassemblies 68-71 .re simultaneously moved inwardly six times during eachevolution of the rotor 30 against centrifugal force and if lesired,against the pressure of a spring 72. During the lortions of each rotorrevolution when pistons 68 are noved radially outwardly by centrifugalforce and spring '2, as permitted by annular cam surface 61, the rotoriassages 59 register with radial passages 58 in distributor read 21, andfuel is pumped by transfer pump 28 into he expanded pressure chamber 60between the pistons. Thus, during each radial reciprocation of pistons68, said ressure chamber is completely refilled with a fixed ruantity offuel from the transfer pump through passages i9.

When pump pressure chamber 60 is full, and whenever nlet passages 58 and`59 are out of register, the fuel lelivered by the transfer pump 28 isreturned to the `upply line, and hence, to the intake side of pump 28hrough pressure regulating valve 27. The latter in the orm showncomprises a transverse valve chamber 73 FIG. 4) which connects at itsopposite closed ends with he lower ends of fuel passages 36 and 51. Ahollow 'alve body 74 houses a piston valve 75 and has an exernal grooveforming an annular chamber 76 in comnunication with fuel supply passage36 and with a leakige fuel bleedback passage 77 connected to the spacetround shaft 26. Piston valve 75 is urged toward the left FIG. 4) acrossa radial port 78 by a spring 79, and aid port is normally covered by thevalve when the transer pump is refilling the pressure chamber 60 of pump29 .s explained above. A peripheral seal may be provided ,t the innerend of body 74 by an O-ring gasket and a pring pressed conical washer80.

When the flow of fuel from pump 28 to pump 29 is nterrupted for anyreason, the full pressure of the fuel lischarged from pump 28 is appliedto valve 75 causing l: to compress spring 79 and to at least partiallyuncover elief port 78. Under these conditions the pressure of the ueldelivered by pump 28 will vary with the speed of the |ump and hence,with the speed of the engine driving haft 26. By properly selecting thecomponent parameters, uch as the rate of spring 79, the contour or shapeof 'ariable orifice 78, and the transverse area of valve 75,

the pressure of the confined fuel may be regulated by valve 27 to varyas a straight line function of the speed (rpm.) of the pump and theengine. The fuel pressure th-us regulated may be used to automaticallyregulate the timing of fuel injection into the engine cylinders and alsoto satisfy the torque backup requirements of the engine with changes inspeed.

A diagonal high pressure fuel passage 81 in rotor 30 connects pumppressure chamber 60 to an axially extending groove 82 in the surface ofthe rotor. During each revolution of the rotor, groove 82 registerssequentially with six equally spaced outlet or delivery passages 83 indistributor head 21 which alternate circumferentially with fuel inletpassages 58. Each of the passages 83 is connected to a differentcylinder of the engine, preferably through a delivery valve 31, only oneof which is shown, mounted in a recess in the distributor head 21 andthe usual injection nozzle at the engine cylinder. The valves 31 may beof any of many well known suitable constructions.

Groove 82 also connects with an annular groove 84 in the surface ofdistributor rotor 30 from which six equally angularly-spaced, radialpassages 85 lead to a central bore 86 in the rotor forming a valvechamber 87. The cylindrical metering or spill valve 32 has a sliding fitin bore 86, but the same is held against rotation with rotor 30 by across pin 88 which extends diametrically through an elongated axiallyextending slot 89 in the reduced hollow stem of the valve that extendsrearwardly from the end of rotor 30 through casing member 22 and intothe bore of a control sleeve 100. Slot 89 permits but limits axialmovement of valve 32 relative to rotor 30 and hence, relative topassages 85. The valve is normally yieldably urged axially toward theleft (FIG. 2) by a preloaded spring 90 to the limit position illustratedin the drawing, with the end of slot 89 engaging pin 88. The latter ispositioned, in a manner to be hereinafter more specifically described,by the sleeve which is in turn positioned axially and angularly by aring nut 98 threaded into casing 22, an end plate 99 and threaded bolts101.

Valve 32 is provided with one or more sets of diverging grooves 91 and92 in the surface thereof arranged for sequential registry with radialpassages 85. Said grooves merge into a single groove 93 near the forwardor left end of the valve and thus communicate with chamber 87. Thelatter is connected =by one or more passages 94 with an annular groove95 in the surface of rotor 30 (FIG. 2) which opens into a radialthrottle valve chamber 96 (FIG. l0) in distributor head 21. Said chamberis suitably connected, such as by a passage 97, to a low pressure sumpor return line to the fuel tank.

In the form illustrated, the throttle valve for varying the speed of theengine comprises a valve member 102 (FIG. 11) having a cylindricalportion 103 and a head portion 113 that is normally seated against aninternal shoulder 105 by a preloaded spring 106. Portion 103 of thevalve is centrally recessed and has a radial port 104 which may, byrotation of the valve member 102, be caused to communicate with fuelreturn passage 97 through a suitably Shaped groove 107 in the outerSurface thereof. The groove 107 may, for example, be an eccentricgroove. It will be seen that port 104 and groove 107 may be variouslyshaped to form, in cooperation with the end of passage 97, an orificefor the spilling or escape of fuel from chamber 96 to the return line97, the size of which orifice will vary with the angular position ofvalve 102.

Angular adjustment of valve 102 may be effected by means of a shaft 108journalled in a sleeve 109 and having an eccentric extension 110 thatengages a radial slot 111 in valve head 113. Shaft 108 and hence, valve102 may be manually rotated by an actuating lever 112 to vary thesetting of escape orice 104, 107. Level 112 is urged by a spring 114 toengine idle position (FIG. l)

against an adjustable stop 115. Another adjustable stop 116 is providedto limit movement of the throttle lever in the other direction, i.e.,clockwise in FIG. 1, to determine the run-out speed at which fuelsupplied to the engine is automatically cut off in a manner to behereinafter described.

The relative angular positions of the pump cam 61, distributor head 21and valve 32 are such that when pump plungers 68 begin to move inwardlyon their pumping stroke, rotor passages 59 will be out of register withinlet passage 58, but groove 82 and hence, passage 81 will be inregister with one of the outlet passages 83. At the beginning of eachpumping stroke, the groove 91 on valve 32 will also be in register witha radial passage 85 and hence, connected to rotor groove 82, 84. Becauseof the high pressure required to open the delivery valve and theinjection nozzle interposed between outlet passage 83 and the enginecylinder, the initial ow of fuel from pump 29 during each pumping strokethereof will take place through passage 81, slot 82, annulus 84, apassage 85 and valve groove 91 into chamber 87 and thence throughpassages 94, annulus 95, and throttle valve orifice 104, as describedabove, to the low pressure fuel return line 97. Upon furthercounterclockwise rotation of the distributor rotor, as viewed from theleft in FIG. 2, the land 117 between grooves 91 and 92 on valve 32 willcover radial passage 85 and cut off ow into chamber 87. The pressure ofthe fuel being delivered by the pump 29 will now rise sufficiently toopen the delivery valve 31 and the injection nozzle at the engine topermit fuel flow to the engine combustion chamber until a passage 85 ofthe rotor 30 moves into registry with groove 92 to again permit fuelflow to the throttle valve orice 104 in the manner above described. Itwill thus be seen that the beginning of injection to an engine cylinderis determined by the angular position of valve groove 91 relative torotor 30 and the passages 85 therein. The duration of each injection atany given engine or pump speed is determined by the circumferentialwidth of land 117 in the plane of passages 85 and hence, upon the axialposition of valve 32 relative to rotor 30. The end of injection isdetermined by registry of groove 92 with a rotor passage 85.

The metering valve 32 and variable orifice throttle valve 102 functionin a novel manner to automatically govern the speed of an enginesupplied by the pump. It will be evident that for any given setting ofvariable throttle orifice 104, 107, the average pressure of the fuelby-passed across valve 32 into chamber 87 will increase as the pumpspeed increases. This results from the fact that for any given positionof valve 32, the quantity of fuel by-passed per unit of time increaseswith rotor speed. Thus, when the rate at which fuel is pumped past valve32 exceeds the rate at which the fuel can escape through throttleorifice 104, the pressure in chamber 87 builds up and causes valve 32 tomove to the right (FIG. 2) against the pressure of spring 90 to`establish equilibrium between the fuel pressure in chamber 87 acting onthe face of valve 32 and the opposing force of the spring. The effectiveportion of land 117 is decreased as valve 32 moves to the right so thatless fuel is injected into the engine cylinder and engine speed isaccordingly reduced. By properly selecting the pre-load and rate ofvalve spring 90 for any given pump and engine, valve 32 will behydraulically actuated by the fuel pressure in chamber 87 to anequilibrium position at which the spill valve land 117 and othersurfaces of the valve between the grooves will cover the s-pill holes 85long enough for the pump to inject sufficient fuel into the enginecylinder to sustain a predetermined engine and pump speed (r.p.m.) undera given load at a given throttle orifice setting. If the engine speedincreases for any reason, the fuel pressure in chamber 87 will increaseand cause movement of valve 32 to the right to effect a reduction offuel delivery to the engine and a consequent reduction in speed. Thereverse operation of valve 32 will occur upon a reduction in enginespeed below that predetermined by the throttle orifice setitng.

As mentioned above, the throttle valve control lever 112 is held inengine idle position against stop assembly by a spring 114. The stopbutton of said assembly is a spring loaded plunger which may be overcomeby applying force in addition to that of spring 114 to move the leverfurther counterclockwise (FIG. l) to its shut-down position. In thisposition, the connection between throttle orifice 104 and passage 97 iscompletely closed, thereby preventing the escape of fuel from valvechamber 87. Accordingly, the pressure builds up and moves valve 32 tothe right to a position such that groove 93 is in the plane of spillholes 85 and in register therewith during the entirety of each pumpingstroke of pump 29. Accordingly, no fuel will then be pumped to theengine cylinders, and operation of the engine will cease.

To avoid a rise in fuel pressure in spill valve chamber 87 in excess ofthe magnitude required to move valve 32 to shut-down position, thethrottle valve 102 functions also as a relief valve. When said pressureexceeds the predetermined maximum, valve 102 is moved thereby to theleft (FIG. 10) against preloaded spring 106 until fuel can escape freelythrough port 104 into the enlarged bore 118 of the valve chamber andthence through a passage 119 to the fuel return passage 97 Novel meansare provided in combination with thepumping and metering apparatusheretofore described for automatically controlling the timing of theinjections into the engine cylinders in response to engine speed. ln thespecific form shown, by way of example, said means comprises atransverse cylinder 120 formed as a part of casing member 22. Saidcylinder has a liner 121 and is closed at its ends by nuts 122 and 123which carry axially adjustable stop bolts 124 and 125, respectively. Atwo-part plunger 126, 127 is slidable in liner 121, and adjacent ends ofthe two parts are Wedge-shaped with transverse semi-circular grooves 128which engage opposite sides of the ball-shaped upper end of pin 88.Liner 121 and casing 22 are provided with registering radial openingsthrough which pin 88 extends from the casing into the cylinder 120.

Movement of plunger 126 toward the right (FIG. l2) is limited byadjustable stop 124 against which it is normally held by a spring 129interposed ybetween plunger member 127 and adjustable stop 125. Cylinder120 to the right of plunger 126 is continuously connected to thedelivery side of transfer pump 28 through passage 130, arcuate groove131, passage 132 (FIGS. 2 and 14), one of passages 58, annulus 56 andIpassages 55, 54 and 51 (FIGS. 8 and 9). Thus, fuel under pressure asregulated by valve assembly 27 acts continuously upon plunger 126 andhence, upon the upper end of pin 8-8 in opposition to spring 129. Thelower end of pin 88 during movement thereof by plunger 126, 127 isguided and maintained perpendicular to the axis of valve 32 by identicaldiametrically disposed slots 133 in the walls of sleeve 100. As shown,each said slot comprises a straight transverse portion 134 and a helicalextension 135, the width of the slot being such as to slidably receivepin 88.

As explained above, the transfer pump delivery pressure acting onplunger 126 is regulated to vary as a straight line function of enginespeed. Accordingly, at a predetermined engine speed the fuel pressureacting on plunger 126 overcomes the preload of spring 129 and causescounterclockwise rotation of pin 88, as viewed in FIG. l2, in atransverse plane and a corresponding rotation of valve 32. This angularmovement or adjustment of said valve relative to distributor rotor 30changes the position of metering groove 91 relative to spill passages 85so as to advance the closing of said passages by land 117 and hence, toadvance the beginning of injections in relation to the cycle of engineoperation. Thus, by proper selection of the pre-load and rate of spring129, automatic variation of injection timing in response to engine speedmay be attained.

The helical portions 13S of slots 133 in sleeve 100 are `rovided fornovelly controlling operation of the pump J satisfy the torque backuprequirement of the engine. for most engines this requirement consists ina reducion, as some function of speed, in the maximum amount lf fuel perinjection which the pump is capable of deivering to the engine, usuallya cut-back in fuel quanity with increased engine speed. Thus, thespecific deign of slots 133 will vary for different engines. As herehown, the helical portions 13S of slots 133 are engaged 'y pin 88 onlyafter some timing advance has been efected in the manner described abovewithout variation f the quantity of fuel delivered per pumping stroke tohe engine. Upon further rotation of pin 88 by plunger 26 in response togreater engine speed, said pin traverses telical portions 135 and hence,has imparted thereto a lnear component of motion toward the right (FIG.2) tlong the axis of valve 32. The valve is thus rotated to urtheradvance the beginning of injection and the pin i8 is moved axially ofsleeve 100 to a position which reults in limiting the movement of valve32 toward the eft (FIG. 2) as determined by engagement of the end lfslot 89 with pin 88 and hence, results in reducing the naximum quantityof fuel per injection that the pump an deliver to the engine.

A socket 136 is provided in casing member 22 (FIG. l) or a suitabletting and fuel return line. The socket comaunicates through passages 137and 138 with low presure fuel passage 97 and the bore of casing 22,respecively, to carry away leakage fuel.

The novel construction and operation of the pump leretofore describedpermit the making of adjustments yt the time of assembly or in the fieldto satisfy the perormance parameters of different engines withoutchanges r1 the basic structure of parts. For example, maximum ueldelivery setting may be varied by varying the posiion of Spanner nut 98in casing 22 to thereby vary the xial position of sleeve 100 and hence,pin 88 to limit he movement of valve 32 toward the left (FIG. 2). Theleginning of injection as related to the profile of delivery ump cam 61may be timed to start at any given cam legree by adjusting plunger stopscrew 124 with the parts n full retard position. The engine speed atwhich a timing ydvance is to begin may also be varied Iby adjustment oftop screw 125 to vary the pre-load on spring 129. The ieginning oftorque cutback in relation to engine speed nay be varied by angularadjustment of cover plate 99 ynd hence, slotted guide sleeve 100, beforetightening the crews 101.

Although only one embodiment of the invention has leen illustrated inthe accompanying drawings and decribed in the foregoing specification,it is to be especially lnderstood that various changes, such as in therelative limensions of the parts, materials used, and the like, as vellas the suggested manner of use of the apparatus of he invention, may bemade therein without departing rom the spirit and scope of theinvention, as will now be tpparent to those skilled in the art.

We claim:

1. In a fuel pump adapted to be used as an injection ump for internalcombustion engines and the like, said ump having a pump body, a rotormounted within the nody, fuel injecting means including pumping meansdislosed within the body and actuated by rotation of the otor relativeto the body for delivering charges of fuel Inder high pressure at spacedintervals, conduit means eceiving the output of the fuel injecting meansand beng adapted to be connected to an engine cylinder through pressureactuated delivery valve interposed in the conluit means in advance ofthe cylinder, and a spill valve vhich is adjustable between two terminalpositions and vhich spills fuel from the conduit means interposed in heconduit means in advance of the delivery valve, the mprovement whichcomprises an axial bore in the rotor, he wall of the bore forming anaxially fixed part of the spill valve, a valve member forming an axiallyand rotatably movable part of the spill valve adjustably mounted withinthe bore in the rotor with its outer wall in sealing confrontingrelationship with the wall of the bore, cooperating port means in thewall of the axial bore in the rotor and in the outer wall of the valvemember, said port means being in communication during parts of each fuelinjection operation of the pumping means, and means to adjust the valvemember to vary the spilling of fuel by the spill valve whereby to varythe beginning and the duration of the injection of fuel into the enginecylinder.

2. A fuel pump according to claim 1, wherein the wall of one of theconfronting parts of the spill valve has a passage therethrough and thewall of the other of the confronting parts of the spill valve has afirst generally axially extending slot therein and a second generallyhelical slot therein converging toward one end of the first slot, thetwo slots defining a generally V-shaped land between them which sealsthe inner end of the said passage in the wall of said one of the partsof the spill valve when the land overlies such inner end of suchpassage, said two slots forming parts of the lpath of the fuel spilledby the spill valve, whereby axial adjustment of the spill valve membervaries the quantity of fuel injected into the engine cylinder by thefuel injecting means, and Whereinthe means to adjust the valve memberadjusts it axially.

3. A fuel pump according to claim 2, wherein the spill valve member isrotatable about its axis to vary the timing of fuel injections into theengine cylinder, and cornprising means responsive to the speed ofrotation of the pump rotor for rotating the spill valve member.

4. A fuel pump according to claim 3, comprising a transfer pump disposedwithin the pump body and driven by the rotor, the transfer pumpdelivering fuel from a fuel source under a low pressure to the pumpingmeans of the fuel injecting means, the said low pressure having asubstantially predetermined relationship to the speed of rotation of therotor.

5. A fuel pump according to claim 4, wherein the means responsive to thespeed of rotation of the pump rotor is responsive to the pressure offuel delivery by the transfer pump.

6. A fuel pump according to claim 5, wherein the means responsive to thepressure of fuel delivered by the transfer pump comprises a cylinderconnected to the output of the transfer pump, a piston reciprocable inthe cylinder, and a spring opposing movement of the piston by the fuelin the cylinder.

7. Fuel injection apparatus for a combustion engine comprising a housinghaving a bore and at least one delivery conduit communicating with saidbore, a normally closed pressure responsive valve in said deliveryconduit, a rotor in said bore forming a fuel cavity around the rotor insaid housing, said rotor having an axial bore, fuel pump means forperiodically pumping fuel to said cavity, said delivery conduit being incommunication with said cavity during a pressure stroke of the pumpmeans, means for rotating the rotor in timed relation with the pumpmeans, metering valve means comprising a cylindrical valve memberslidable in said rotor bore, means comprising said valve member androtor bore forming an expansible spill cavity, a port in the wall of therotor and an axially extending first groove in the surface of said valvemember registrable with said port during a pumping stroke of the pumpmeans for connecting said cavities and thereby bypass fuel from saiddelivery conduit, whereby fuel pressure in said spill cavity urges saidvalve member in one direction axially relative to the rotor, means forcon trolling the escape of fuel from the spill cavity to a low pressurespace, and resilient means under compression for urging said valvemember axially in the other direction relative to the rotor inopposition to the fuel pressure in said spill cavity.

8. Apparatus as defined in claim 7, wherein the parameters of the partsare such that the opposing pressures exerted by said resilient means andby the fuel in said spill cavity are equalized when the rotor isrotating at a preselected speed.

9. Apparatus as defined in claim 8, wherein said valve member is movableaxially by said resilient means and by the fuel pressure in the spillcavity when the rotor speed is less and greater, respectively, than saidpreselected speed.

10. Apparatus as defined in claim 7, wherein said pump means comprisesopposed radial pistons and means responsive to rotation of said rotorfor actuating said pistons.

11. Apparatus as defined in claim 10 comprising a passage in said rotorconnecting the pressure chamber of the pump means and said fuel cavity.

12. Apparatus as defined in claim 7 comprising a fuel transfer pump insaid housing having rotor means coaxial with and drivably connected tosaid rotor, conduit means including a passage in said rotor forperiodically connecting the delivery outlet of said pump to the pressurechamber of said pump means between pressure strokes of the latter, andmeans responsive to the fuel pressure in said conduit means forangularly adjusting said valve member relative to said rotor.

13. Apparatus as defined in claim 7 comprising a second groove in thesurface of said valve member and registrable with said port during apumping stroke of the pump means, said first and second groovesconverging to form a common groove at the ends thereof communicatingwith said spill cavity.

1,4. Apparatus as defined in claim 13, wherein movement of said port outof registry with said second groove determines the beginning of fueldischarge from the fuel cavity through said delivery conduit.

15. Apparatus as defined in claim 13, wherein said first groove ishelical and registry of said port therewith determines the end of fueldischarge from said fuel cavity through said delivery conduit.

16. Apparatus as defined in claim 7, wherein said means for controllingthe escape of fuel from the spill cavity comprises variable fiowrestricting orifice means.

17. Apparatus as defined in claim 16 comprising means for selectivelyvarying the size of said orifice means.

18. Apparatus as defined in claim 7, wherein said means for controllingthe escape of fuel from the spill cavity includes means for selectivelypreventing escape of fuel from said spill cavity to said low pressurespace, whereby the valve member is moved axially by fuel pressure in thespill cavity to a terminal position at which said fuel and spillcavities are connected through said port and grooves during the entirepressure stroke of the pump means.

19. Fuel injection apparatus for a combustion engine comprising ahousing having a bore and at least one delivery passage communicatingwith said bore, a normally closed pressure responsive valve in saiddelivery passage, a rotor in said bore forming a fuel cavity around therotor in said housing, said rotor having an axial bore, fuel pump meansfor periodically pumping fuel to said cavity, said delivery passagebeing in communication with said cavity during a pressure stroke of thepump means, means for rotating the rotor in timed relation with the pumpmeans, metering valve means comprising a cylindrical valve memberslidable in said rotor bore, and port means in the wall of the rotor andfirst and second grooves in the surface of said valve member cooperablewith said port means during a pressure stroke of the pump means forconnecting said cavity to a low pressure space and thereby by-pass fuelfrom said delivery passage, whereby fuel is discharged through saiddelivery passage only -when said port means is closed by the rotorsurface between said grooves during said pressure stroke.

20. Apparatus as defined in claim 19, wherein said grooves extendgenerally axially of the valve member at an acute angle to each other.

21. Apparatus as defined in claim 20, wherein the direction of rotationof the rotor is such that said port means moves across said first andsecond grooves in that order and the discharging of fuel through thedelivery passage begins when said port means .moves out of registry withsaid iirst groove and the discharging of fuel through said deliverypassage ends when said port means moves into registry with said secondgroove.

22. Apparatus as defined in claim 20 comprising resilient means urgingsaid valve member toward a position to effect maximum fuel dischargethrough said delivery passage.

23. Apparatus as defined in claim 22 comprising means for adjusting saidvalve member axially and angularly relative to the rotor.

24. Apparatus as defined in claim 23, wherein said means for adjustingsaid valve member comprises hydraulic means responsive to the speed ofrotation of the rotor.

25. Apparatus as defined in claim 22 comprising means responsive to thespeed of rotation of the rotor for moving said valve member axiallyrelative to the rotor in opposition to said resilient means to vary thequantity of fuel discharged through the delivery passage during apressure stroke of the pump means.

26. Apparatus as defined in claim 22 comprising means responsive to thespeed of rotation of the rotor for moving said valve member angularlyrelative to said rotor to vary the beginning of fuel discharge throughthe delivery passage during a pressure stroke of the pump means.

27. In a fuel pump adapted to be used as an injection pump for internalcombustion engines and the like, said pump having a pump body, a rotormounted Within the body, fuel injecting means including pumping meansdisposed -within the body and actuated by rotation of the rotor relativeto the body for delivering charges of fuel under high pressure at spacedintervals, first conduit means receiving the output of the fuelinjecting means and being adapted to be connected to an engine cylinderthrough a pressure actuated delivery valve interposed in the firstconduit .means in advance of the cylinder, and a metering spill valvewhich is adjustable between first and second terminal positions andwhich spills fuel from the rst conduit means interposed in the firstconduit means in advance of the delivery valve to control the quantityof fuel injected into the engine at each fuel injecting operation of thepumping means, the improvement which comprises a fuel transfer pumpdriven with the rotor and having an inlet adapted to be connected to afuel source, a second conduit means delivering fuel from the outlet ofthe transfer pump to the inlet of the fuel injecting means, the partsbeing so constructed and arranged that the pressure of fuel delivered bythe transfer pump varies in response to rotor speed, third conduit meansreceiving fuel spilled by the metering valve and returning it to a lowpressure space, means having a restricted orifice interposed in thethird conduit means in advance of the low pressure space, and means foradjusting the metering valve comprising means responsive to the pressureof the thus spilled fuel in the third conduit means in advance of saidorifice for urging the metering valve toward its first terminalposition, and yieldable means for constantly urging the metering valvetoward its second terminal position.

28. A fuel pump according to claim 27 wherein the transfer pump isdisposed -within the body and is drivably connected with the rotor.

29. A fuel pump according to claim 27 wherein the metering spill valvecomprises an axial bore in the rotor, the wall of the bore forming anaxially fixed part of the metering valve, a valve member adjustablymounted within the bore in the rotor with its outer wall in sealingconfronting relationship with the wall of the bore and cooperating portsin the Wall of the axial bore in the rotor and in the wall of the valvemember, said ports being in communication during a part of each fuelinjection operalll ion of the pumping means, and the means for adjustinghe metering valve comprises means to adjust the valve nember to vary thespilling of fuel by the metering valve vhereby to vary the injection offuel into the engine zylinder.

30. A fuel pump according to claim 29 wherein the vall of the bore inthe rotor has a passage therethrough ind the wall of the valve member ofthe metering valve las a rst generally axially extending slot thereinand a econd generally helical slot therein converging toward ne end ofthe rst slot, the two slots defining a generally I -shaped land betweenthem which seals the inner end of he said passage when the land overliesthe inner end if the passage, said two slots forming parts of the path fthe fuel spilled by the metering valve, whereby axial tdjustment of themetering valve member varies the quanity of fuel injected into theengine cylinder by the fuel njecting means, and the means for adjustingthe metering 'alve moves the valve member axially within the bore in herotor.

31. A fuel pump according to claim 29 wherein said irst terminalposition of the adjustable metering valve is hat of maximum fuel flowtherethrough, and the second erminal position thereof is that of minimumfuel flow herethrough, whereby the speed of the engine under vari- Ybleload is held at a substantially constant speed which s determined by theeffective area of the orifice.

32. A fuel pump according to claim 29 wherein the neans having arestricted orice comprises an adjustable hrottle valve, whereby theengine speed may be varied y adjustment of the orifice through saidthrottle valve.

33. A fuel pump according to claim 29 comprising a ressure relief valveconnected to the third conduit means to prevent undue pressure build uptherein upon engine shut-down.

34. A fuel pump according to claim 27 wherein the means responsive tothe pressure of fuel spilled by the metering valve comprises andexpansible chamber within the rotor formed by the bore in the rotor andthe end of the valve member in said bore -which confronts the inner endof the bore.

35. Apparatus as defined in claim 18 comprising pressure relief valvemeans operable to connect said spill cavity to a low pressure space inresponse to fuel pressure in the spill cavity in excess of that requiredto move the valve member to said terminal position.

References Cited UNITED STATES PATENTS 2,465,138 3/1949 Van-Tuyl 103-372,831,473 4/1958 Liuolet 123-1401 2,839,999 6/1958 Shallenberg 103-373,025,797 3/1962 Hutcheon 103-2 3,035,523 5/1962 Kemp et al 103--23,314,406 4/1967 Kemp et al 103-2 3,368,490 2/1968 Virello 123-1393,381,615 5/1968 Bailey 103-2 3,427,979 2/1969 Kemp 103-2 3,437,0424/1969 Kemp 103-41 3,228,339 l/1966 Evans et al. 103-2 HENRY F. RADUAZO,Primary Examiner U.S. Cl. X.R. 103-5, 37; 123-139

